1. Field of the Invention
The present invention is related to a fluorene-based pyrimidine-containing conjugated oligomer for organic light-emitting device.
2. Description of the Prior Art
In the known technical field of organic light-emitting materials when a small molecule compound is used as the organic light-emitting material, crystallization usually occurs due to the molecular of the compound is too small and its structure is too symmetrical. Therefore, when applied as an organic light-emitting material, the small molecule compound is vulnerable to crystallization, and once the crystal is formed, it yields negative impacts upon the light-emitting nature and service life of the OLED. Such flaws caused by the restriction from the compound structure cannot be easily overcome and eliminated.
Furthermore, those valance electrons involving in the bonding process is another existing problem to the organic light-emitting device since the they when excited to become free electrons, they form a hole and the hole has a greater moving rate and that of the electrons, resulting in reduced chance for further bonding or if bonded, that takes place in a layer of the device not pre-determined. In terms of a structure of an organic light-emitting device (1) as illustrated in FIG. 1 of the accompanying drawings, an electron-transport layer and a hole transport layer (3) are respectively connected to an electric field (6) through a metal cathode (4) and an indium tin oxide (ITO) anode (5), given with the externally applied electric filed, electrons from the electron transport layer (2) and the hole from the hole transport layer (3) both enter into an organic light-emitting layer (7) to further bond into excitons to release the energy and return to the ground level. In the course of releasing the energy, it is representing by lights of various colors depending on the material used for the organic light-emitting layer (7). Before the moving rate of the electron become optimal, if the reaction of the further bonding fails to present in the organic light-emitting layer (7), the electroluminescent efficiency is naturally compromised and deprived of the value of the OLED for industrial purpose.